Lyocell fibre and film is produced by dissolving cellulose in a suitable solvent, for example a tertiary amine N-oxide such as N-methyl morpholine oxide mixed with water. A suitable method of manufacture is described in U.S. Pat. No. 4,416,698. The solution of cellulose in the amine oxide solvent, which is solid at ambient temperature, is extruded at a temperature of 95-1250.degree. C. from a spinneret or film die through an air gap into a precipitation bath of water or dilute aqueous amine oxide, and the amine oxide solvent leaches into the bath, producing cellulose fibre or film.
JP-A-8-170224 discloses a biconstituent fibre of the islands-in-the-sea type in which the continuous "sea" component is a cellulose-type polymer spun from an organic solvent system and the "islands" are composed of a polymer dyeable by a disperse dye and are 0.01-34 .mu.m in size and form 2-45% by weight of the fibre. The disperse dyeable polymer is for example a polyester such as polyethylene terephthalate, sulphonic acid-modified polyethylene terephthalate or polybutylene terephthalate.
GE-A-2121069 discloses cellulose-based (viscose rayon) fibres for the Production of nonwovens containing as mineral fillers barium sulphate, talcum, muskovite, or a mixture thereof, in an amount of from 15 to 60%, preferably 40 to 50%, of the total fibre mass, and, if desired, additionally hydrophobic, polymer or oligomer substances, such as polyethylene, polypropylene, polystyrene, polyacrylic acid ester, polyester, polytetrafluoroethylene or waxes, in an amount of from 1 to 60%, preferably 25 to 50%, of the total fibre mass. GB-A-2008126 discloses the use of polystyrene as a delustrant for viscose rayon fibres.